Lecture 1

Question 1

Identification vs Diagnosis

Answer 1

-Identification: identifying that there is a problem (e.g., hearing loss, vestibular problem, problems hearing at school)
-Diagnosis: determining the nature of the condition (based on assessment). This may or may not include etiology (underlying cause of the condition)
·E.g., a moderate sloping to severe sensorineural hearing loss bilaterally

Question 2

T/F: audiologists can diagnose hearing loss

Answer 2

TRUE (though you can’t diagnose in Ontario)

Question 3

What does the Y axis represent in audiometry?

Answer 3

-dB HL (air and bone)
-Loudness contours and growth
-Intensity discrimination

Question 4

What does the X axis represent in audiometry?

Answer 4

-Frequency
-Place specificity
-The basalward shift

Question 5

What does the Z axis represent in audiometry?

Answer 5

-Time
-Temporal integration

Question 6

What is the purpose of the audiogram?

Answer 6

-Provides information about likely communication problems
-Critical for audiologic treatment

Question 7

What are some limits of audiometry? (4)

Answer 7

-Poor for distinguishing sensory versus neural loss
-May miss significant loss of hair cells
-Does not assess temporal processing
-It is the beginning of assessment, not the end

Question 8

What is behavioural audiometry?

Answer 8

-Functional characterization of clinically relevant psychoacoustic details
-Goal is not description of ability, but description of different ability

Question 9

Do outer ear effects play an important role in diagnostics?

Answer 9

Yes, we get a big enhancement from our concha, pinna and ear canal at around 2-5 kHz with minimal audible field (MAF)

Question 10

T/F: shape of hearing reflects ME and OE

Answer 10

TRUE

Question 11

T/F: the natural shape of the absolute threshold curve (i.e., the MAP) is important for diagnostics

Answer 11

FALSE: the natural shape is NOT relevant for diagnostic purposes

Question 12

What is dB HL?

Answer 12

-dB HL is a flattened version of the MAP
-dB HL = dB SPL - RETSPL (reference equivalent threshold sound pressure level)

Question 13

What are RETSPLs?

Answer 13

-Levels in dB SPL that correspond to 0 dB HL, as measured at a calibration point
·Inserts: 2cc coupler
·TDH: 6cc coupler
·Speakers: microphone in centre of head

Question 14

T/F: hearing loss looks worse (higher thresholds) when you have smaller ears

Answer 14

FALSE: smaller ear canals lead to greater pressure reaching your eardrum, resulting in better thresholds

Question 15

What is the leak problem with inserts?

Answer 15

Drop in hearing in the lower frequencies because the foam inserts aren’t in tight enough

Question 16

With a perforation, does that impact thresholds more when using inserts or sound field?

Answer 16

Inserts, because the increase in pressure will cause a greater effect than in the real world (sound field)

Question 17

What are the 5 mechanisms of bone conduction?

Answer 17

-Sound radiating into the external ear canal
·Occlusion effect when ears are plugged
-Middle ear ossicle inertia
-Inertia of the cochlear fluids
·Most important source
-Compression of the cochlear walls
-Pressure transmission from the cerebrospinal fluid

Question 18

T/F: BC thresholds can be worse than AC thresholds

Answer 18

TRUE: really small ear canals could cause AC to be better than BC and really large ear canals could cause an air-bone gap without any conductive loss

Question 19

Where does loudness grow most quickly on the equal loudness contours?

Answer 19

Low frequencies

Question 20

Loudness ___ with a 10 dB increase (Stevens)

Answer 20

Doubles

Question 21

According to RM Warren, doubling loudness corresponds to ___ dB

Answer 21

6

Question 22

What is loudness recruitment?

Answer 22

-With cochlear hearing loss, loudness tends to grow more quickly
-When one ear is normal, recruitment can be detected with the alternate binaural loudness balance (ABLB) test

Question 23

What is the SISI (short-increment sensitivity index)?

Answer 23

-Count the number of 1 dB changes identified (out of 20) at 20 dB SL
-If you can hear them, recruitment is diagnosed

Question 24

T/F: Weber’s law does not hold for pure tones

Answer 24

TRUE: level discrimination improves at high levels

Question 25

What is the problem with SISI?

Answer 25

-The SISI test always diagnoses recruitment because loudness discrimination is naturally better at high levels (the “near miss to Weber’s law”)
-It has NO clinical value for diagnosing recruitment

Question 26

What causes recruitment in hearing loss?

Answer 26

Inability to hear soft sounds is a function of loss of mechanical amplification (OHCs) for soft sounds

Question 27

T/F: place specificity is poor at low levels

Answer 27

FALSE: it’s poor at high levels

Question 28

The primary determinants of hearing sensitivity are ____

Answer 28

Peripheral (structure of middle ear, basilar membrane, etc)

Question 29

Thresholds are stable as long as tones are longer than ___ second

Answer 29

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